Antenna system



W. L. CARLSON ANTENNA. SYSTEM Filed Jan. 28, 1942 k mShNQmk 3rmcntor Gttotueg Wendell L; Carlson Patented Jan. 30, 1945 ANTENNA SYSTEM Wendell L. Carlson. Haddonfield, N. J., assignor to Radio Corporation of America, a corporation of Delaware Application January 28, 19-12, Serial No. 428,521

3 Claims.

My invention relates to directive antenna systems and particularly to a high frequency antenna system for receiving or transmitting horizontally polarized waves, the antenna being directive in any one of a plurality of preselected directions.

An object of the invention is to provide a simple and eiiective directive antenna system that may be switched readily to receive from or transmit in any one of a number of directions.

In a preferred embodiment of the invention the antenna is utilized for reception and comprise three quarter-wave dipole conductors or rods located in a horizontal plane and spaced 120 degree apart. Switching means is provided to enable an operator to employ any two of the dipole rods together as an antenna (one rod being unused) or any one of the dipole rods in combination with the other two rods connected together so that the other two rods function as the equivalent of one rod bisecting the 120 degree angle between them. In this way, the antenna can be made directive in any one of six different directions.

The invention will be better understood from the following description taken in connection with the accompanying drawing in which Figure 1 shows a diagram of one embodiment of the invention, and

Figures 2a to 2 are diagrams showing the directive characteristics of the antenna for the various switching positions.

In Fig. 1, the antenna comprises three quarter-wave dipole rods I, 2 and 3 located radially with respect to each other in a horizontal plane and positioned 120 degrees apart. Conductors 6, 1 and 8 lead from the dipole rods l, 2 and 3, respectively, to switch arms H, i2 and i3.

As indicated schematically, the switch. arms ll, l2 and I3 are ganged so that they may be rotated about a common pivot by rotating a switch knob [4. As they are rotated, they make contact, successively, with switch contact points l6, l1, I8, I9 and 2|. Points l6 and I9 are connected by a bus bar or conductor 22. Points ll, 18 and 21 are connected by a bus bar or conductor 23. Each bus bar is connected to the radio receiver 24 or other apparatus utilizing the antenna.

With the switch in the position illustrated, the antenna rods I and 2 are connected to the receiver and the rod 3 is not being used. Thus, the antenna functions as shown in Fig. 2b and the directive pattern is as indicated by the dotted lines. If the switch is rotated counter clockwise one step, the rods I and 2 are connected together by the bus bar 23 and the rod 3 is connected to the bus bar 22. This is the connection illustrated in Fig, 2e, the antenna now being directive in a different direction as shown by the dotted lines.

It will be apparent from inspection that the antenna rods 2 and 3 may be switched to any one of the connections shown in Figs. 2a to 2 to make the antenna directive in any one of the six directions indicated by the dotted lines.

I claim as my invention:

1. An antenna system comprising three antenna conductors or rods located radially with respect toeach other in a plane and positioned substantially degrees apart, and switching means for utilizing as a directive antenna any two of said rods alone or any one of said rods in combination with the other two rods connected together whereby the antenna system may be made directive in any one of six directions.

2. The invention according to claim 1 wherein said rods are located in a horizontal plane.

3. An antenna system for a receiver having two input terminals comprising three antenna conductors or rods located radially with respect to each other in a horizontal plane and positioned substantially 120 degrees apart, and switching means connecting any two of said rods to said two receiver terminals, respectively, or any one of said rods to one of said terminals and the other two rods to the other of said terminals.

WENDELL L. CARLSON. 

